ESS20-0 Datasheet, PDF (1/6 Pages) ETAL Group – Selective load protection with physical isolation in the event of a fault

Electronic Circuit Breaker ESS20-0...
Description
Electronic circuit breaker type ESS20-0.. is designed to ensure
selective disconnection of individual loads in systems which are
powered by a DC 24 V switch-mode power supply.
DC 24 V power supplies, which are widely used in industry today, will
shut down the output in the event of an overload with the result that
one faulty load in the system can lead to complete disconnection of
all loads. As well as an unidentified failure this also means stoppage
of the whole system.
Through selective disconnection the ESS20-0.. responds much
faster to overload or short circuit conditions than the switch-mode
power supply. This is achieved by a combination of active current
limitation and well-proven circuit breaker technology including
physical isolation. The ESS20-0.. limits the highest possible current
to 1.8 or 1.5 times the selected rated current of the circuit breaker.
Thus it is possible to switch on capacitive loads of up to 75,000 µF
lamp loads, but they are disconnected only in the event of an overload
or short circuit.
ESS20-0..
Technical data (Tambient = 25 °C, operating voltage US = DC 24 V)
Operating data
For optimal adjustment to the application conditions the current rating
of the ESS20-0.. can be selected in fixed values from 0.5 A...10 A and
in adjustable variants 1 A/2 A or 3 A/6 A. Failure and status indication
are provided by a bicolour LED and an integral signal contact.
Operating voltage U_S
Current rating I_N


DC 24 V (18...32 V)
fixed current ratings: 0.5 A, 1 A, 2 A, 3 A,
4 A, 6 A, 8 A, 10 A
switchable: 1 A/2 A or 3 A/6 A
The ESS20-0.. features a width of only 12.5 mm and can be plugged
into the E-T-A power distribution socket Module 17plus and SVSxx
(for ESS20-003) ensuring ease of installation and saving space in
Power consumption
Trip current (bimetal)

typically 13 mA
typically 0.3 A
(only in the event of a failure, before physical isolation)
control cabinets.
Status indication
by means of
Bicolour LED:
Green: unit is ON, power-MOSFET is
US patent number: US 6,490,141 B2


switched on
Orange: in the event of overload or

short circuit until physical isolation
Features


LED not lighted: push button in OFF
position
l Selective load protection with physical isolation in the event of a fault.
l All types of loads can be connected (small DC motors etc. on



potential-free signal contact (change-
over contact)
OFF-position of push button
4
request).
l Active current limitation (1.8 or 1.5 times rated current I_N = 8 A or
10 A) for safe connection of capacitive loads up to 75,000 µF and
on overload/short circuit.
l Electronic trip characteristic.
l Reliable overload disconnection with 1.1 x I_N plus, even with long
load lines or small cable cross sections (see table 2).
l Selectable current ratings (fixed values 0.5 A...10 A or two steps:
1 A/2 A or 3 A/6 A).
Reverse polarity
protection of U_S
Load circuit
internal bimetal (fail-safe element) trips,
push button moves into OFF position
Load output

Power-MOSFET switching output
(high side switch)
Max. data of load
with side-by-side mounting see table 1
Voltage drop at I_N
see table 1
l Manual ON/OFF button (push-push actuation).
Overload disconnection
typically 1.1 x I_N (1.05...1.35 x I_N)
l Clear status and failure indication.
l Width per unit only 12.5 mm.
Short-circuit current I_K

typically 1.8 x I_N / active current
limitation
l Plug-in mounting utilising power distribution system Module 17plus
or SVSxx (for ESS20-003), see product group 7.
Trip time
see time/current characteristics
for physical isolation
typically 5 sec at I_load > 1.1 x I_N
for electronic disconnection typically 5 sec...100 ms at I_load > 1.8 x I_N
Approvals

or 1.5 x I_N
Temperature disconnection internal temperature monitoring with

physical isolation
Authority
VDE
UL
Norm
EN
60934
UL 1077
Voltage ratings
DC 32 V
DC 28 V
Current ratings
0.5 A…10 A
0.5 A…10 A
Low voltage monitoring
load output OFF at U_S < 7 V
ON at U_S >16 V
Starting delay t_start

typically 0.3 sec after every switch-on
and after applying U_S
Notes
l The user should ensure that the cable cross sections of the relevant
load circuit are suitable for the current rating of the ESS20 used.
l Automatic start-up of machinery after shut down must be prevented
(Machinery Directive 98/37/EG and EN 60204-1). In the event of
a short circuit or overload the load circuit will be disconnected
electronically by the ESS20.
Disconnection of load circuit single pole (switch contact)

- by push-push actuation of the blue
push button

- upon electronic fault disconnection
(overload, short circuit)

- with reverse polarity
Free-wheeling circuit

external free-wheeling diode
recommended with inductive load
Several load outputs must not be connected in parallel.
1646
www.e-t-a.de
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